There is a real danger of genetic abnormality, stillbirth, or significant disability. Scientists are also pointing out that there is no evidence that Zavos has in fact cloned a human embryo.

Zavos is also trying to create animal-human hybrids. He is putting DNA from a dead girl into cow eggs to try to produce hybrid embryos. Zavos says that he will not transfer these cowgirls into a woman. He is experimenting to improve the technique. Nevertheless, he suggests that putting DNA first into a cow egg and then later into a human egg might make cloning more efficient. So he is thinking of transferring material from hybrid embryos into a woman.

It is worth noting that this same method of making animal-human hybrid embryos has just been legalised in the United Kingdom. In the debates over the human fertilisation and embryology bill politicians repeatedly stated that hybrid embryos were important for research on diseases such as Parkinson's and Alzheimer's. I suspected at the time that the whole hybrid-embryo story was a mixture of hype and cruel deception. Tellingly, immediately after the bill was passed, the Medical Research Council announced it would not fund the proposed hybrid embryo research.

It is very unlikely that Dr Zavos will succeed in what he is trying to do. However, the creating of animal-human hybrid embryos may prove helpful to Zavos or to others who follow him. It is hard to tell. It would be a bitter irony if an ethically dubious technique, legalised despite its ineffectiveness in research, proved to be an effective step towards the first clone baby.

What though would be wrong with cloning a baby, if we could overcome the safety problems? For one thing, cloning would create an unfair burden of expectation on any child. Of course every child both benefits from the hopes and suffers from the expectations of their parents. On the positive side most parents I know try to encourage their children to develop their talents. I think of my colleagues ferrying children back from swimming practice or orchestra. On the other side I have friends who suffered from living their parents' dreams rather than their own and who have spent much of their adult life trying to recover from this.

A clone would live his or her whole life in the shadow of someone who had already lived. The existing pressures of expectation on children are bad enough. How much worse to be born as a clone? Worse still to be the cloned replacement for a child who had died. You could never be that child. You cannot replace the irreplaceable. Not even Dr Zavos can raise a child from the dead.